When Reign returns on the small screen this fall, fans can expect plague, famine, and a feisty new character: British actress Rose Williams will join the cast as a recurring guest star.

Williams will play Princess Claude, the royal daughter of Catherine de Medici and the deceased King Henry and sister to the newly crowned King Francis.

According to The CW, “Claude is a glorious troublemaker who sees other women primarily as competition, and delights in making one woman’s life a living hell: her mother’s.” Does this mean the conniving Catherine has finally met her match?

Williams—a Hollywood newcomer who appeared on an episode of the BBC show Casualty earlier this year—may not be the only new addition to Reign’s cast. At TCA, star Adelaide Kane teased the possibility of new villains—make that “new gentlemen”—on the period drama’s upcoming season.